buckingham



(No Model.) 2 Sheets-Sheet 1.

' G L. BUOKINGHAM.

EECULATCE FOR DYNAM ELECTRIC MACHINES. No. 294,307. Patented Feb. 26, 1884.

N. Pncus. Phclu-Lilhogrnphur. Washingium n. c

(No Model.) 2 Sheets-Sheet 2.

'G. L. BUCKINGHAM. REGULATOR FOR DYNAMO ELECTRIC MACHINES.

No. 294.307. Patented Feb. 26, 1884.

WITNESSES Ururan STATES PATENT CHARLES L. BUCKINGHAM, OF NEIV YORK, X. Y.

REGULATOR FOR DYNAMO-ELECTRIC WlAQl-HNES.

SPECIFICATION forming part of Letters Patent No. 294,307, dated February 26, 1884.

Application filed December 17, 1883. (No model.)

T0 aZZ whom it may concern..-

Be it known that I, GHinLns L. BUCKING- Han, of the city, county,- and State of New York, a citizen of the United States, have invented anew and useful Improvement in Regulators for Varying the Field-Magnetism of a Dynamo-Electric Machine, of which the following is a specification.

It is generally necessary that the speed of rotation of the armature of the dynamo-electrio machine and of the engine driving the armature be uniform. If the field-magnetism were also uniform, the electro-motive force of the dynamoanachine would be invariable, and a current of electricity directed to a workingcircuit would be variable and inversely proportional to its resistance.

The object of my invention is to render the field-magnetism automatically variable and the electro-motive force of the dynamo-machine always proportional to the resistance of the external or working circuit by a novel method and apparatus,whereby a more nearly uniform strength of current in the workingcircuit may be obtained than has heretofore been accomplished. To this end I divide at least one-half of the field-coils into many sections, and provide each of said subdivisions with a pole-changer, whereby each section may have its terminals reversed by the operation of its pole-changer, thereby enabling a current flowing through the field-coils to pass through the section in a direction opposite to that which it would have had before the operation of the pole-changer. By this means the magnetic effects due to any section of the fieldcoils is reversed upon the operation of the pole-changer, and one pole-changer after another, in succession, throughout the series, may be operated, when the iieldanagnetism will be rendered m'Z, providing one-half of all the field-coils have been reversed. The polechangers are controlled by an electro-magnet or electro-magnets whose coils form a part of the working-circuit, or whose action is controlled thereby. If the additional resistance of one or more electric lamps be inserted in said circuit, the current strength will be eorrespondingly diminished, or, it a like resistance be removed from circuit, the current strength will be increased. In either case one or more of the pole-changers will be operated. If resistance be inserted, a coil-section of the holdmagnet must be so reversed as to augment the field-magnetism rather than neutralize apart. 5 5

If resistance be removed, a coil-section must be so reversed that a coil which before served to augment the field magnetism may not only not contribute to strengthen the field, but will neutralize a part of the magnetism due to the remainder of the fieldcoils.

I will 110w describe my invention by reference to the accompanying drawings Figure 1 represents my improved regulator with the lield-coils in the shunt-circuit D in 6 5 respect to the external or working circuit, and the electromagnetic devices for controlling the regulator are placed in and form apart of the external circuit, L. Fig. 2 represents my regulator in connection with field-coils,which,

together with devices for controlling the regulator, form parts of the working-circuit.

For convenience of illustration, I have shown four sets of reversible field-coils (though it may be necessary to employ more) longitudinally 7 arranged along the field-cores. If tield-magnets having four limbs, a, I), c, and d, be used, it is obvious that upon a reversal ofcurrentthrough any one of the field-coils, providing said coils were wound entirely upon one limb, as limb a of the cores of the field-magnet, the poles of the field-magnets would be displacedfor example, the pole S would be displaced to the right. To avoid such displacement, I make each section of the field-coils comprise four individual or component coils, so arranged that normally the coils 2 and 3, for instance, produce a north pole at the middle of I) c, and the coils l and i a south pole at the middle of a d, and in like manner every reversible coil- 0 section is symmetrically arranged upon the fieldeores.

In practice, instead of winding coils l 2 34 at the extremities of the field-poles, and 5 6 7 8 longitudinally within and adjoining coils second, third, and fourth reversible coil-section may be wound in superposed layers over the first.

A is an armature of a dynamo-electric 1na I chine, adapted to rotate in the hollowedout space between the poles of the field-magnet, having a commutator, O, and brushes B B. From brush B the main line L passes through electro-magnets M N O P, and thence through a series of electric lights or other electrical translators to the opposite commutator-brush, B. From brush B the circuit 1), when armature-levers Q 1 S T,which are respectively pivoted at points at a; w .r,are intheir retracted positions, has its path first through the large non-reversible coil, and then to the pivot or point u, hammer m, spring 0, field-coils 1 23 4, lever f, anvil g, thence to pivot or point e, and in like manner through all of the reversible coils to the opposite commutator-brush, B.

The pole-changers of the regulator are in position for all of the lamps Z to be inserted in circuit, and the main-line resistance will then be so far increased as to weaken the current sufficiently to permit the retraction of all of the pole-changing armatures. Under this condition the reversible coils all conspire to produce a maximum strength of fieldanagnetism. If one or more lights I were removed from circuit, the main-line current would be increased and one or more of the armature-levers Q, R S T (and that armature-lever would first be attracted which is adjusted to respond to the weakest current) would be attracted to their electro-magnets. If Q were attracted, hammer m would be raised and lever f lifted from anvil g, and f would then rest upon or, and 0 against 9. The current in branch D then, instead of flowing from u in the direction 1 2 3 4, would pass through said coils from a in the direction 4 3 2 1. In the same way the current through coils 5 6 7 8, or other section, may be independently reversed. The current therefore may be reversed in the several sections successively andretained so reversed through all of said sections.

The adjustingsprings of the various polechanging arms should be arranged to respond to slightly-different strengths of current, in order that they may be brought into action successively, but not simultaneously 5 otherwise reversals and re-reversals of two or more fieldsections might intermittently occur, whereby the field-magnetism would be momentarily varied to a large extent rather than by such small amounts as would be nearly proportional to changes in resistance in the working-circuit.

It is obvious that upon a movement of a pole-changing arm the field-section connected therewith is first cut out of circuit and afterward reversed. By this means, in the process of reversal of a field-section, the field-magnet ism is first reduced by the cutting out of the same, and still further by its reversal. It will also be seen, if each of the pole-changing arms, as Q, were only sufficiently moved to permit spring 6 to come in contact with anvil g without raising spring f from said anvil, that each field-section would only be cut out of circuit, or short-'eircuited, instead of being reversed.

As shown in Fig. 2, the field-coils are placed in series with the coils of the armature in the working-circuit, and also the coils of the mag net M. M has an axial armature, H, which controls a lever, V, pivoted at m and has at its opposite end a long contact-arm, whereby as armature H is attracted connection may be made between n and one or all of a series of contact-strips, 20, to close the branches of the local battery L B, including local magnets for controlling the pole-changers of the coil-sections of the field-magnets. It is obvious that, instead of placing the magnets for controlling the pole-changers in the working-circuit, they may be placed in a circuit derived from the working-circuit.

Fig. 3 shows a mechanical device, controlled by magnet M, for operating the pole-changers, one at a time. Lever V is provided with a segment of gear-teeth, 0, which mesh with the teeth of pinion 1). Upon the same shaft, q, with p is a disk, 1', having a camgroove, s, in its face. One portion of the cam-groove is in the are of a circle, and is of large circumference, while the remaining part of said groove is of small circumference, and is likewise in the arc of a circle. The ends of the pole-changing arms normally rest in that partof the groove of large circumference. If, however, the disk r be rotated by the action of armature H, the pole-changing arms will pass, one at a time, into the other part of the groove, and thereupon cause the sections of field-coils to be successively reversed. A reverse movement of H will cause a reversal of the fieldsections.

That I claim, and desire to secure by letters Patent, is

1. In a dynamo-electric machine, the combination of a series of coil-sections of the fieldmagnets, and a series of pole-changers for reversing the circuit through any one or all of the coil-sections, and means, controlled by va riations of current in the working-circuit, to operate said pole-changers.

2. The combination of a reversible coil-section of the field-magnets, a pole-changer for reversing said coil-section, and an electromagnet controlled by variations of resistance in the working-circuit, to operate said polechanger.

3. The combination of a reversible coil-section of the field-magnets, a pole-changer for reversing said coil-section, and an electro-magnet placed in the working-circuit, for controlling said pole-changer.

at. The combination of a series of field magnet sections whose component parts are symmetrically arranged, substantially as described,

a polechanger for reversing said section, and w an electromagnet for controlling said polechanger by variations of current in the working-circuit.

5. The combination of a series of reversible field-magnet sections, a corresponding series of independent pole-changers, a mechanical device for operating said pole-changers in sue said mechanical device for controlling thepoleplaced in the working-circuit, a series of circhangers. omit-controlling arms, Q. R S T, a series of field- 6. The combination of a series of field-11mg coil sections, and means for bringing said 5 net sections and a corresponding series of dearms snccessivelyinto operation, substantially I5 vices, each of which is adapted to short-ciras specified. cuit its corresponding ficldsection, a mechan- CHARLES L. BUOKINGHAM. ical apparatus for operating said devices, and ll'itnesses: an electronnagnet placed in the working-cir- GEO. H. FEARONS,

cession, and an elect-ro-magnet for cont-rolling 7. The combination of electro-inagnet M,

i 1o cult,forcontrollingsald mechanical apparatus. 1 S. S. WATTERs. 

